WASHINGTON (Reuters) - A deep green fungus best known for
eating through uniforms and canvas tents during World War Two
might provide a more efficient way to make biofuels such as
ethanol, researchers reported on Monday.

They sequenced the complete genome of Trichoderma reesei
and found important clues about how it breaks down plant fibers
into the simple sugars needed to make plant-based fuel.

While its appetite for cotton and other fibrous plants
caused trouble for troops in the South Pacific, the fungus
might provide a way to use switchgrass and other nonfood plants
to make biofuels, the researchers reported in the journal
Nature Biotechnology.

One barrier to using nonfood plants to make biofuels has
been the difficulty in converting them into sugar. Food crops
such as corn more readily convert.

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"Our analysis, coupled with the genome sequence data,
provides a road map for constructing enhanced T. reesei strains
for industrial applications such as biofuel production," Diego
Martinez of Los Alamos National Laboratory in New Mexico and
colleagues wrote.

The fungus has already been exploited commercially. "It has
enjoyed a long history of safe use for industrial enzyme
production," they wrote.

But the genetic analysis overturned some assumptions about
how it worked.

It uses enzymes it creates to break down plant fibers into
the simplest form of sugar, known as a monosaccharide. But it
has fewer genes dedicated to the production of cellulose-eating
enzymes than other fungi do.

"We were aware of T. reesei's reputation as producer of
massive quantities of degrading enzymes. However we were
surprised by how few enzyme types it produces, which suggested
to us that its protein secretion system is exceptionally
efficient," Martinez, who is also at the University of New
Mexico, said in a statement.

T. reesei could be grown on an industrial scale to secrete
its fiber-eating enzymes, which in turn could be added to
pulped-up plants to produce sugar. The sugar can then be
fermented by yeast to produce ethanol.

"The information contained in its genome will allow us to
better understand how this organism degrades cellulose so
efficiently and to understand how it produces the required
enzymes so prodigiously," said Joel Cherry of Danish-based
Novozymes, a biotechnology company that took part in the study.

"Using this information, it may be possible to improve both
of these properties, decreasing the cost of converting
cellulosic biomass to fuels and chemicals," Cherry said.